677
FXUS63 KLMK 061040
AFDLMK

Area Forecast Discussion
National Weather Service Louisville KY
640 AM EDT Sun Jul 6 2025

...Updated Aviation Discussion...

.KEY MESSAGES...

* Hot today, with isolated to scattered storms possible in the
  afternoon and evening. Afternoon heat index values near 100.

* Humidity and rain chances increasing in earnest Monday through
  most of the upcoming work week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 322 AM EDT Sun Jul 6 2025

Upper ridging will continue to slowly weaken overhead today. A mid-
level shortwave will swing east over the Great Lakes and Midwest. A
sfc cold front currently stretching from Upper MI to KS will sink
southeast from Lower MI to central MO by 00Z this evening. A plume
of enhanced low-level moisture reaching north through western TN and
west-central KY was partly responsible for the development of
isolated convection in our southwestern forecast area last evening.
This moisture axis continues to gradually spread north and east
through central KY and southern IN today.

The majority of new convection will be across MO, IL, and IN today
ahead of the approaching synoptic boundary. However, richer low-
level moisture, strong sfc heating, and relatively weaker capping
will result in isolated showers and storms across central KY and
southern IN. Very weak flow aloft will produce pulse single cells,
and convective outflow will foster new updrafts. Lightning, locally
gusty winds, and brief heavy rain will be possible with any pulse
storm.

Localized downpours will bring relief from the heat to a lucky few.
Temperatures will again warm into the low 90s area-wide this
afternoon, with a few spots pushing into the mid 90s. Somewhat
higher humidity today will yield afternoon heat index values near
100. Heat-related impacts are a concern for those without adequate
cooling/hydration.

Isolated to scattered showers and storms could linger well past
sunset in southern IN. Skies will range from partly cloudy to mostly
clear overnight, with lows in the low to mid 70s.

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 322 AM EDT Sun Jul 6 2025

Weak mid-level shortwave troughing moves over the region on Monday
as the sfc cold front sinks into the Ohio Valley. Deeper moisture
pooling ahead of the boundary and increased forcing will result in
at least scattered showers and storms. Deep shear will remain too
weak for organized strong convection. However, torrential rainfall
and locally gusty winds will be possible during the afternoon and
evening hours. The added moisture in the environment will begin to
constrict the diurnal temperature range. Look for highs in the upper
80s to low 90s.

On Tuesday, we are in between shortwave disturbances, with the next
wave approaching the Mid-MS Valley. The plume of higher precipitable
water slips south a bit, with the best chance for scattered PM
convection across central KY. Rain chances taper to a Slight Chance
as you move north into central Indiana.

An upper level shortwave trough slowly amplifies as it moves over
the region Wednesday into Thursday. A humid airmass will remain in
place, with daily chances for showers and storms. Storm chances will
peak during the afternoon and evening hours, with highs in the mid
80s to around 90 and lows in the upper 60s and low 70s.

&&

.AVIATION /12Z TAFS THROUGH 18Z MONDAY/...
Issued at 639 AM EDT Sun Jul 6 2025

SCT-BKN mid clouds around 10-12 kft will linger between I-65 and I-
75 this morning, followed by a diurnal cumulus field in the
afternoon. Other than some brief MVFR fog early this morning at BWG,
prevailing VFR conditions are likely through much of this TAF
period. Southwesterly winds will increase to 7-11 kts this afternoon
ahead of a frontal boundary sinking southeast through the Midwest.

Isolated TSRA development is possible this afternoon and evening,
but coverage looks too low to include at most terminals. Did go
ahead and include a PROB30 group at HNB, where coverage could be
just slightly higher this evening.

&&

.LMK WATCHES/WARNINGS/ADVISORIES...
KY...None.
IN...None.

&&

$$

SHORT TERM...EBW
LONG TERM...EBW
AVIATION...EBW